Wheelchairs and other mobility devices provide disabled persons with equipment to be mobile and to increase opportunities for these persons to participate more fully in daily activities. Typical wheelchairs provide a chassis with wheels and include a cushioned seat and back seating system. The wheelchairs may be powered or self-propelled by pushing on the wheels.
Persons requiring this equipment often are seated in wheelchairs for long periods of time. Extended seating in a single position however leads to muscle fatigue. To provide relief from seating pressures of the body on the seating cushions, the positioning of the individual in the seat is changed to provide pressure relief and reduce fatigue. A fatigued person in a wheelchair tends to slump. This leads to bad posture. Fatigue and bad posture can lead to physical problems such as poor blood circulation, skeletal difficulties, and pressure sores.
To address this problem, mobility devices were provided with seating systems that could be tilted or re-positioned relative to the mobility base in order to change the position of the body relative to the seat. This re-positioning changes the contact area of the body to the seating surface and tends to reduce the pressure problems and fatigue problems noted above.
Traditional wheelchairs with adjustable tilt of seating required a long wheel base. This is because the mobility devices had to accommodate a rear fulcrum against which the seat would rotate. The long wheel base prevents the chair from tipping. While such wheelchairs provide tilting of seating relative to the chair, there are drawbacks to the use. In particular, the chair tends to be significantly heavier than a wheelchair which does not have seating which is tiltable. The wheelchair is typically larger. This makes the wheelchair more difficult to transport. The longer wheel base increases the turning radius which complicates maneuvering the wheelchair inside buildings.
Accordingly, there is a need in the art for an improved seating system for wheelchairs providing tilting of the seating relative to the wheelchair while maintaining the center of gravity and positioning relative to the seating. It is to such that the present invention is directed.